Design of a lightweight passenger seat using composite materials to reduce vehicle weight, emissions, and improve fuel economy

Abstract

This research investigates the design and analysis of a lightweight passenger seat frame for a 13 seat Toyota Hiace minibus, utilizing a hybrid composite material to reduce vehicle weight, emissions, and improve fuel economy. The primary objective is to replace the conventional high strength steel seat frame with a novel hybrid composite consisting of Carbon Fiber Reinforced Polymer (CFRP), flax fiber, and epoxy resin in a 40:30:30 volume ratio. The methodology integrates Computer-Aided Design (CAD) in SOLIDWORKS, Finite Element Analysis (FEA) via ANSYS Workbench for structural and modal evaluation, and a longitudinal vehicle dynamics model simulated in Python to quantify fuel consumption and emissions. Material properties for the hybrid composite were determined using the Rule of Mixtures. The results demonstrate an 83.6% reduction in the total mass of the 13-seat assembly, from 126.75 kg (steel) to 20.8 kg (composite), while maintaining structural integrity with a minimum safety factor of 5.89. This weight saving leads to a predicted 1.5-2.5% improvement in highway fuel economy, translating to an annual reduction of approximately 15 liters of fuel and 40 kg of CO₂ emissions per vehicle. The study confirms the hybrid composite seat frame as a viable, multi-functional component that successfully balances mass reduction, structural performance, and sustainability.